NATURAL SCIENCES OF PHILADELPHIA. 9] 



near affinity, while Heteraetus melanoleucus (Vieill.) heads the 

 list! Messrs. Sclater & Salvin, in their "Nomenclator Avium Neo- 

 tropicalium" 1 (pp. 118-119), include all the species of Buteo and 

 Graxirex in the genus Buteo, with the exception of B. brachyura, 

 which is assigned to the special genus u Buteola," a procedure 

 which is entirely unwarranted by the characters of the bird. Mr. 

 Gray, in his "Hand List of Birds" 2 (I., pp. 6-9), makes the distinc- 

 tion between the subgenus Buteo (as he restricts it) and its allies 

 strictly a geographical one, no true Buteo belonging, according 

 to his classification, to the American continent. The subgenus 

 Graxirex is made to include, besides the appropriate species, 

 Buteo borealis, B. lineatus, B. cooperi, and Anterior unicinctus I 

 The subgenus " Tachytriorchis" contains B.leucops ( = C. gala- 

 pagoensis,juv.), B. abbreviatus (given in the list as " 63 albonota- 

 <ms" and " 65 zonocercus"), besides B. u pterocles" (= albicaudatus), 

 B. erythronotus, and B. poliosomus, which are true Craxireces. 



Having thus explained the proper limits of the subgenus 

 Graxirex, I now present a synopsis of the species, briefly show- 

 ing the distinguishing characters of each. 



Synojjsis of Sjyecies. 



A. Wing very long, the tips of the primaries reaching nearly or 

 quite to the end of the tail. Tail of young crossed b} r very 

 numerous (eleven to seventeen) very narrow and indistinct 

 bars of dusky. Size, large (wing more than 12.00 inches). 



a. Tail of adult grayish-brown, tipped with fulvous, and crossed 



with thirteen bars of blackish. 



1. G. galapagoensis. Bill very large, much elongated, with 

 its horizontal outlines nearly parallel. Adult. Sooty-black, 

 the primaries glossed with ashy and barred with blackish- 

 brown, and the lining of the wing tinged with rufous. 

 Wing, 15.15-17.30; tail, 9.20-11.00; culmen, 1.25; tarsus, 

 2.65-3.35; middle toe, 2.10. Hab. Galapagos Islands. 



b. Tail of adult white, crossed by narrow lines of slate-gray and 



with a very broad subterminal band of slate-black. 



2. G. poliosomus. Bill smaller, less elongated, and with the 

 upper outline more ascending basally. Adult. Bluish-slate; 

 lores whitish ; tail-coverts white, barred and mottled with 



! London, 1873. 2 London, 1869. 



